Distribution of the pulmonary artery and vein in the lung of the white handed gibbon

The lungs of four white handed gibbons (Hylobates agilis) were examined. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then traverses the dorsal side of the right middle lobe bronchiole. Thereafter, it runs along the dorso-lateral side of the right bronchus, between the dorsal bronchiole system and the lateral bronchiole system, and gradually follows the dorsal side of the right bronchus. During its course, it gives off arterial branches which run along each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole and then along the left bronchus as in the right lung. The branches of the pulmonary artery run mainly along the dorsal or lateral side of the bronchiole, while the pulmonary veins run mainly the medial side of the bronchioles or between them. However, in a few portions, the pulmonary veins run the lateral side of the bronchioles. Finally, they enter the left atrium with four large veins i.e. the common trunk of the right upper lobe vein and right middle lobe vein, right lower lobe pulmonary venous trunk, left middle lobe vein, and left lower lobe pulmonary venous trunk.     

Distribution of the pulmonary artery and vein in the chimpanzee lung

Lungs of two chimpanzees (Pan troglodytes) were examined. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole and, then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal bronchiole system and the lateral bronchiole system, along the right bronchus. During its course, it gives off arterial branches which run along each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole and then between the dorsal bronchiole system and the lateral bronchiole system. The branches of the pulmonary artery run mainly along the dorsal or lateral side of the bronchiole. The pulmonary veins run mainly along the ventral or medial side of the bronchioles, and between them. Finally, they enter the left atrium with four large veins, i.e. the common trunk of the right upper lobe vein and the right middle lobe vein, right lower lobe pulmonary venous trunk, left middle lobe vein, and left lower lobe pulmonary venous trunk.     

猕猴肝门静脉系统和肝静脉系统的观察

以铸型方法及实体解剖观察了猕猴(Macaca mulatta) 肝的门静脉分支和肝静脉分支。猕猴肝门静脉与人、猪、兔、牛、羊等相似, 同样可将全肝分成二叶四段, 即左叶、右叶; 左外侧段、左内侧段、右内侧段、右外侧段。尾状叶的左、右部可分别隶属于左叶和右叶。猕猴肝大静脉有左外侧叶肝静脉、左内侧叶肝静脉、肝中静脉、肝右静脉及尾状叶肝静脉。此外, 作者对哺乳动物门静脉分支的规律性, 猕猴肝大静脉的命名及吻合作了讨论。     

The bronchial tree and blood vessels of the Japanese monkey lung

The author injected various colored celluloid solutions into the bronchial tree and blood vessels of the lungs of five adult Japanese monkeys (Macaca fuscata) in order to prepare cast specimens. These specimens were investigated from the comparative anatomical viewpoint to determine whether the bronchial ramification theory of the mammalian lung (Nakakuki, 1975, 1980) can be applied to the Japanese monkey lung or not. The bronchioles are arranged stereotaxically like those of other mammalian lungs. The four bronchiole systems, dorsal, ventral, medial, and lateral, arise from both bronchi, respectively, although some bronchioles are lacking. In the right lung, the bronchioles form the upper, middle, accessory, and lower lobes, while in the left lung, the upper and accessory lobes are lacking and bi-lobed middle and lower lobes are formed. In the right lung, the upper lobe is formed by the first branch of the dorsal bronchiole system. The middle lobe is the first branch of the lateral bronchiole system. The accessory lobe is the first branch of the ventral bronchiole system. The lower lobe is formed by the remaining bronchioles of the four bronchiole systems. In the left lung, the middle lobe is formed by the first branch of the lateral bronchiole system. The lower lobe is formed by the remaining bronchioles. Thus, the bronchial ramification theory of the mammalian lung applied well to the Japanese monkey lung. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole. It then runs along the dorso-lateral side of the right bronchus between the dorsal bronchiole system and the lateral bronchiole system. On its way, it gives off branches of the pulmonary artery which run along the dorsal or lateral side of each bronchiole except in the ventral bronchiole system. In the ventral bronchiole system, the branches run along the ventral side of the bronchioles. The distributions of the pulmonary artery in the left lung are the same as those in the right lung. The pulmonary veins do not always run along the bronchioles. Most of them run on the medial or ventral side of the bronchioles. Some of them run between the pulmonary segments. In the right lung, these pulmonary veins finally form the right upper lobe vein, right middle lobe vein and the right lower lobe pulmonary venous trunk before entering the left atrium. However, the right accessory lobe vein runs on the dorsal side of the bronchiole and pours into the right lower lobe pulmonary venous trunk. In four cases out of the five examples, part of the right lower lobe veins pour into the right middle lobe vein, while the others enter the right lower lobe pulmonary venous trunk. In the left lung, the branches of the pulmonary veins finally form the left middle lobe vein and the left lower lobe pulmonary venous trunk.     

Lack of alveolar O2 during lung reperfusion does not decrease edema formation

We previously reported that pulmonary arterial occlusion for 48 h followed by 4 h of reperfusion in awake dogs results in marked edema and inflammatory infiltrates in both reperfused and contralateral lungs (Am. Rev. Respir. Dis. 134: 752-756, 1986; J. Appl. Physiol. 63: 942-950, 1987). In this experiment we study the effects of alveolar hypoxia on this injury. Anesthetized dogs underwent thoracotomy and occlusion of the left pulmonary artery. Twenty-four hours later the dogs were reanesthetized, and a double-lumen endotracheal tube was placed. The right lung was continuously ventilated with an inspiratory O2 fraction (FIO2) of 0.35. In seven study animals the left lung was ventilated with an FIO2 of 0 for 3 h after the left pulmonary artery occluder was removed. In six control animals the left lung was ventilated with an FIO2 of 0.35 during the same reperfusion period. Postmortem bloodless wet-to-dry weight ratios were 5.87 +/- 0.20 for the left lower lobe and 5.32 +/- 0.12 for the right lower lobe in the dogs with hypoxic ventilation (P less than 0.05 for right vs. left lobes). These values were not significantly different from the control dog lung values of 5.94 +/- 0.22 for the left lower lobe and 5.11 +/- 0.07 for the right lower lobe (P less than 0.05 for right vs. left lobes). All values were significantly higher than our laboratory normal of 4.71 +/- 0.06. We conclude that reperfusion injury is unaffected by alveolar hypoxia during the reperfusion phase.     

Distribution of the pulmonary artery and vein in the lung of the crab-eating monkey (Macaca fascicularis)

In the lung of the crab-eating monkey (Macaca fascicularis), the right pulmonary artery runs across the ventral side of the right upper lobe bronchiole and the dorsal side of the right middle lobe bronchiole. Thereafter, it courses along the dorso-lateral side of the right bronchus, between the dorsal and lateral bronchiole systems. During this course, the right pulmonary artery gives off arterial branches running mainly along the dorsal or lateral side of each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole, and is then distributed as in the right lower lobe. The pulmonary veins run mainly along the ventral or medial side of the bronchiole in the upper and middle lobes whereas, in the lower lobe, they run ventrally, and between the bronchioles. Finally they enter the left atrium as four large veins.     

Hypoxic pulmonary vasoconstriction does not affect hydrostatic pulmonary edema formation

We studied the effects of regional hypoxic pulmonary vasoconstriction (HPV) on lobar flow diversion in the presence of hydrostatic pulmonary edema. Ten anesthetized dogs with the left lower lobe (LLL) suspended in a net for continuous weighing were ventilated with a bronchial divider so the LLL could be ventilated with either 100% O2 or a hypoxic gas mixture (90% N2-5% CO2-5% O2). A balloon was inflated in the left atrium until hydrostatic pulmonary edema occurred, as evidenced by a continuous increase in LLL weight. Left lower lobe flow (QLLL) was measured by electromagnetic flow meter and cardiac output (QT) by thermal dilution. At a left atrial pressure of 30 +/- 5 mmHg, ventilation of the LLL with the hypoxic gas mixture caused QLLL/QT to decrease from 17 +/- 4 to 11 +/- 3% (P less than 0.05), pulmonary arterial pressure to increase from 35 +/- 5 to 37 +/- 6 mmHg (P less than 0.05), and no significant change in rate of LLL weight gain. Gravimetric confirmation of our results was provided by experiments in four animals where the LLL was ventilated with an hypoxic gas mixture for 2 h while the right lung was ventilated with 100% O2. In these animals there was no difference in bloodless lung water between the LLL and right lower lobe. We conclude that in the presence of left atrial pressures high enough to cause hydrostatic pulmonary edema, HPV causes significant flow diversion from an hypoxic lobe but the decrease in flow does not affect edema formation.     

Distribution of the pulmonary artery and vein of the orangutan lung

The distribution of the pulmonary artery and vein of the orangutan lung was examined. The right pulmonary artery runs obliquely across the ventral side of the right bronchus at the caudally to the right upper lobe bronchiole. It then runs across the dorsal side of the right middle lobe bronchiole. Thereafter it runs obliquely across the dorsal side of the right bronchus, and then along the dorso-medial side of the right bronchus. This course is different from that in other mammals. During its course, it gives off branches which run mainly along the dorsal or lateral side of each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole, then along the dorso-lateral side of the left bronchus, giving off branches which run along each bronchiole. The pulmonary veins run mainly the ventral or medial side of, along or between the bronchioles. In the left lung, the left middle lobe vein has two trunks; one enters the left atrium, and the other enters the left lower lobe pulmonary venous trunk. This is also different from that found in most mammals. Finally, the pulmonary veins enter the left atrium with four large veins.     

The bronchial tree,lobular division,and blood vessels of the lung of the silvered lutong (Presbytis cristata)

The lungs of three silvered lutongs (Presbytis cristata) were examined. The right and left lungs have the dorsal, lateral, ventral, and medial bronchiole systems, which arise from the corresponding sides of both bronchi, respectively. Bronchioles in the dorsal and lateral bronchiole systems are well developed, whereas those in the ventral and medial bronchiole systems are poorly developed and lack some portions. According to the fundamental structure of bronchial ramifications of the mammalian lung (Nakakuki, 1975, 1980), the right lung consists of the upper, middle, lower, and accessory lobes, whereas the left lung consists of a bilobed middle lobe and a lower lobe, in which the right upper lobe is extremely well developed. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe bronchiole. Initially it runs along the lateral side of the right bronchus and then gradually comes to run along the dorsal side. During its course, it gives off branches which run mainly along the dorsal or lateral side of the bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole, and then follows the same course as that in the right lower lobe. The pulmonary veins run medially or ventrally to the bronchioles, and finally enter the left atrium as four or five large veins.     

Development of a Simple Reliable Radiographic Scoring System to Aid the Diagnosis of Pulmonary Tuberculosis

Rationale

Chest radiography is sometimes the only method available for investigating patients with possible pulmonary tuberculosis (PTB) with negative sputum smears. However, interpretation of chest radiographs in this context lacks specificity for PTB, is subjective and is neither standardized nor reproducible. Efforts to improve the interpretation of chest radiography are warranted.

Objectives

To develop a scoring system to aid the diagnosis of PTB, using features recorded with the Chest Radiograph Reading and Recording System (CRRS).

Methods

Chest radiographs of outpatients with possible PTB, recruited over 3 years at clinics in South Africa were read by two independent readers using the CRRS method. Multivariate analysis was used to identify features significantly associated with culture-positive PTB. These were weighted and used to generate a score.

Results

473 patients were included in the analysis. Large upper lobe opacities, cavities, unilateral pleural effusion and adenopathy were significantly associated with PTB, had high inter-reader reliability, and received 2, 2, 1 and 2 points, respectively in the final score. Using a cut-off of 2, scores below this threshold had a high negative predictive value (91.5%, 95%CI 87.1,94.7), but low positive predictive value (49.4%, 95%CI 42.9,55.9). Among the 382 TB suspects with negative sputum smears, 229 patients had scores <2; the score correctly ruled out active PTB in 214 of these patients (NPV 93.4%; 95%CI 89.4,96.3). The score had a suboptimal negative predictive value in HIV-infected patients (NPV 86.4, 95% CI 75,94).

Conclusions

The proposed scoring system is simple, and reliably ruled out active PTB in smear-negative HIV-uninfected patients, thus potentially reducing the need for further tests in high burden settings. Validation studies are now required.     

Role of pulmonary blood flow in postpneumonectomy lung growth.

To study the influence of blood flow on postpneumonectomy lung growth, we banded the left caudal lobe pulmonary artery of eight ferrets in such a way that blood flow to the caudal lobe did not increase when the right lung was excised 1 wk later. The fraction of the cardiac output received by the right lung before pneumonectomy was therefore directed entirely to the left cranial lobe. Three weeks after pneumonectomy the weight, volume, and protein and DNA contents of the two lobes of the left lung were measured and compared with those of five unoperated animals and eight animals after right pneumonectomy alone. Although its perfusion did not increase after pneumonectomy, the left caudal lobe of banded animals participated in compensatory growth, increasing in weight and protein and DNA contents. Although the cranial lobe of banded animals received 25% more of the cardiac output than the same lobe in pneumonectomized animals, cranial lobe volume and protein and DNA contents in the two groups were similar. Caudal lobes were smaller in banded than in simple pneumonectomized animals and tended to contain less protein, whereas the cranial lobes tended to be heavier. We conclude that increased pulmonary perfusion is not necessary for compensatory lung growth in adult ferrets, but it may modify this response.     

The bronchial tree,lobular division,and blood vessels of the lung of the Diana monkey (Cercopithecus diana)

The authors examined the lung of one Diana monkey (Cercopithecus diana). The right lung consists of upper, middle, lower, and accessory lobes, the upper and middle lobes being united dorsally. The accessory and lower lobes are separated from the other lobes by fissures. The left lung consists of a bi-lobed middle lobe and a lower lobe. These lobes are separated by an interlobular fissure. The Diana monkey has dorsal, lateral, ventral, and medial bronchiole systems on either side. The upper lobe is formed by the first bronchiole of the dorsal bronchiole system. The middle lobe is formed by the first bronchiole of the lateral bronchiole system and the accessory lobe is formed by the first bronchiole of the ventral bronchiole system. The remaining bronchioles of the four bronchiole systems constitute the lower lobe. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal and lateral bronchiole systems, along the dorso-lateral side of the right bronchus. During its course, the right pulmonary artery gives off arterial branches running along the dorsal or lateral side of each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole. Thereafter, it follows the same course as in the right lung, giving off arterial branches. The pulmonary veins run along the ventral or medial side of the bronchiole, and between the bronchioles.     

肺炎型肺癌的影像学特点及误诊分析

目的:探讨肺炎型肺癌影像学特点,深入肺炎型肺癌认识,提高诊断水平,降低临床误诊率。方法:随机选取2013年1月份至2014年2月份我院胸外科住院治疗的36例肺炎型肺癌患者作为研究对象,回顾性分析全部患者的影像学资料及病理检查结果。结果:患者病变部位在各肺段均有分布,局限性及弥漫性分布均可见,其中局灶性分布较大,未出现跨越肺段侵袭肺叶的病例。影像表现主要为边缘不清云絮状肿块影、云絮状影伴结节、肺段实变影、肺实变伴空泡及蜂窝状影、肺炎纤维样化及混合阴影。其中,单纯性磨玻璃影10例;磨玻璃结节肿块10例;肺段分布实变影7例;肺叶及肺段实变伴空泡或蜂窝状影6例;肺炎样纤维化及肿块10例;混合阴影(4种或4种以上阴影并存)3例。结论:肺炎型肺癌患者影像学检查结果多具有肺炎样改变,极易误诊肺炎性疾病,临床诊断中结合活检检查技术,有利于改善临床诊断正确率。     

Mechanisms by which dopamine alters blood flow distribution during lobar collapse in dogs

Dopamine increases blood flow to a hypoxic left lower lobe in dogs. To elucidate possible mechanisms, left lower lobe collapse was induced in anesthetized dogs, and lobar (QLLL) and total (QT) pulmonary blood flow was measured by electromagnetic flow probes. Dopamine infusion increased mean pulmonary arterial pressure (Ppa), QT, and QLLL. However, the increase in QLLL was double that produced by a similar increase in Ppa without increase in QT (inflation of a Swan-Ganz balloon in right pulmonary artery) or by a similar increase in QT with smaller increase in Ppa (opening of arteriovenous fistulas). QLLL/QT was not changed by opening arteriovenous fistulas, but was increased by Swan-Ganz balloon inflation, and by infusion of dopamine. It is concluded that the increase in QLLL/QT produced by dopamine was due to a decrease in hypoxic vasoconstriction in the lobe secondary to an increase in mixed venous PO2 and to vasoconstriction in the oxygenated lung.     

The lobular division,bronchial tree and blood vessels of the squirrel monkey lung

The lobular division, bronchial tree, and blood vessels in lungs of seven squirrel monkeys (Saimiri sciureus) were examined from the viewpoint of comparative anatomy. The right lung of the squirrel monkey consists of the upper, middle, lower, and accessory lobes, whereas the left lung consists of the upper, middle, and lower lobes. These lobes are completely separated by interlobular fissures. In three of seven examples examined the left middle lobe was lacking. The squirrel monkey lung has four bronchiole systems, i.e. dorsal, lateral, ventral, and medial, on both sides. The upper lobes are formed by the first branches of the dorsal bronchiole systems. The middle lobes are formed by the first branches of the lateral bronchiole systems. The remaining bronchioles constitute the lower lobes. In addition to the above lobes, in the right lung, the accessory lobe is present, being formed by the first branch of the ventral bronchiole system. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal bronchiole and lateral bronchiole systems along the dorso-lateral side of the right bronchus. During its course, the right pulmonary artery gives off the arterial branches which run along each bronchiole. These branches run mainly along the dorsal or lateral side of the bronchioles. In the left lung, the pulmonary artery and its branches run the same course as in the right lung. The pulmonary veins run mainly the ventral or medial side of the bronchioles, and between the bronchioles.     

Prevalence of Pulmonary Tuberculosis among Adults in a North Indian District

BackgroundRecent population prevalence estimates of pulmonary tuberculosis (PTB) are not available for several areas in India. We conducted a field-based population survey at a north Indian district to estimate point prevalence of bacteriologically positive PTB.MethodsA stratified cluster sampling design was used to conduct the survey in both urban and rural areas within the district. All adults aged more than 15 years, in 18 rural and 12 urban clusters of 3000 subjects each, were interviewed using a symptom card. Two sputum samples were collected from all persons having symptoms suggestive of PTB, or history of antitubercular treatment, for smear microscopy for acid-fast bacilli and mycobacterial culture. Those having at least one sputum specimen positive on microscopy and/or culture were categorized as having PTB. Prevalence was estimated after adjusting for cluster sampling and incomplete data (through individual level analysis with robust standard error).ResultsOf 91,030 eligible adult participants (47,714 men and 43,316 women), 85,770 (94.2%) completed the symptom cards. Of them, 2,898 persons were considered eligible for sputum examination and 2,839 (98.0%) provided at least one sample. Overall, 21 persons had bacteriologically positive PTB, and cluster level prevalence was estimated at 24.5 per 100,000 population (95% CI 12.8–36.2). Individual level analysis with robust standard error yielded a prevalence estimate of 24.1 per 100,000 populations (95% CI 12.8–35.4).ConclusionThe observed prevalence of bacteriologically positive PTB in this district is lower than empiric national estimates, probably as a result of successful implementation of tuberculosis control measures in the area.     

<Emphasis Type="Italic">Cryptococcus gattii</Emphasis> Infection Presenting as an Aggressive Lung Mass

Cryptococcus gattii is an endemic fungus predominantly isolated in the tropical and subtropical regions, causing predominantly pulmonary disease with a predilection for the central nervous system. Herein, we report a case of rapidly progressing C. gattii pneumonia in an immune-deficient but virologically suppressed host with underlying human immunodeficiency viral (HIV) infection, exhibiting various fungal morphologies from bronchoalveolar lavage (BAL) cytological specimens. A 51-year-old Chinese male with known HIV disease was admitted to the Singapore General Hospital for evaluation of functional decline, febrile episodes, and a left hilar mass on chest radiograph. Computed tomography (CT) showed consolidation in the apical segment of the left lower lobe. He underwent bronchoscopy and BAL. Positron emission tomography-computed tomography done 10 days after the initial CT showed approximate doubling of the pulmonary lesion. Cytological examination of the fluid revealed yeasts of varying sizes. Subsequent fungal culture from BAL fluid grew C. gattii 10 days later.     

Effect of regional alveolar hypoxia on permeability pulmonary edema formation in dogs

We studied the effects of regional alveolar hypoxia on permeability pulmonary edema formation. Anesthetized dogs had a bronchial divider placed so that the left lower lobe (LLL) could be ventilated with a hypoxic gas mixture (HGM) while the right lung was continuously ventilated with 100% O2. Bilateral permeability edema was induced with 0.05 ml/kg oleic acid and after 4 h of LLL ventilation with an HGM (n = 9) LLL gross weight was 161 +/- 13 (SE) g compared with 204 +/- 13 (SE) g (P less than 0.05) in the right lower lobe (RLL). Bloodless lobar water and dry weight were also significantly lower in the LLL as compared with the RLL of the study animals. In seven control animals in which the LLL fractional inspired concentration of O2 (FIO2) was 1.0 during permeability edema, there were no differences in gravimetric variables between LLL and RLL. In eight additional animals, pulmonary capillary pressure (Pc), measured by simultaneous occlusion of left pulmonary artery and vein, was not significantly different between LLL FIO2 of 1.0 and 0.05 either before or after pulmonary edema. We conclude that, in the presence of permeability pulmonary edema, regional alveolar hypoxia causes reduction in edema formation. The decreased edema formation during alveolar hypoxia is not due to a reduction in Pc.     

Pulmonary Abnormalities in Mice with Paracoccidioidomycosis: A Sequential Study Comparing High Resolution Computed Tomography and Pathologic Findings

Background

Human paracoccidioidomycosis (PCM) is an endemic fungal disease of pulmonary origin. Follow-up of pulmonary lesions by image studies in an experimental model of PCM has not been previously attempted. This study focuses on defining patterns, topography and intensity of lung lesions in experimentally infected PCM mice by means of a comparative analysis between High Resolution Computed Tomography (HRCT) and histopathologic parameters.

Methodology

Male BALB/c mice were intranasally inoculated with 3×10⁶ Paracoccidioides brasiliensis (Pb) conidia (n = 50) or PBS (n = 50). HRCT was done every four weeks to determine pulmonary lesions, quantify lung density, reconstruct and quantify lung air structure. Lungs were also analyzed by histopathology and histomorphometry.

Results

Three different patterns of lesions were evidenced by HRCT and histopathology, as follows: nodular-diffuse, confluent and pseudo-tumoral. The lesions were mainly located around the hilus and affected more frequently the left lung. At the 4^th week post-challenge HRCT showed that 80% of the Pb-infected mice had peri-bronchial consolidations associated with a significant increase in upper lung density when compared with controls, (−263±25 vs. −422±10 HU, p<0.001). After the 8^th and 12^th weeks, consolidation had progressed involving also the middle regions. Histopathology revealed that consolidation as assessed by HRCT was equivalent histologically to a confluent granulomatous reaction, while nodules corresponded to individual compact granulomas. At the 16^th week of infection, confluent granulomas formed pseudotumoral masses that obstructed large bronchi. Discrete focal fibrosis was visible gradually around granulomas, but this finding was only evident by histopathology.

Conclusions/Significance

This study demonstrated that conventional HRCT is a useful tool for evaluation and quantification of pulmonary damage occurring in experimental mouse PCM. The experimental design used decreases the need to sacrifice a large number of animals, and serves to monitor treatment efficacy by means of a more rational approach to the study of human lung disease.     

Pressure load: the main factor for altered gene expression in right ventricular hypertrophy in chronic hypoxic rats

Background

The present study investigated whether changes in gene expression in the right ventricle following pulmonary hypertension can be attributed to hypoxia or pressure loading.

Methodology/Principal Findings

To distinguish hypoxia from pressure-induced alterations, a group of rats underwent banding of the pulmonary trunk (PTB), sham operation, or the rats were exposed to normoxia or chronic, hypobaric hypoxia. Pressure measurements were performed and the right ventricle was analyzed by Affymetrix GeneChip, and selected genes were confirmed by quantitative PCR and immunoblotting. Right ventricular systolic blood pressure and right ventricle to body weight ratio were elevated in the PTB and the hypoxic rats. Expression of the same 172 genes was altered in the chronic hypoxic and PTB rats. Thus, gene expression of enzymes participating in fatty acid oxidation and the glycerol channel were downregulated. mRNA expression of aquaporin 7 was downregulated, but this was not the case for the protein expression. In contrast, monoamine oxidase A and tissue transglutaminase were upregulated both at gene and protein levels. 11 genes (e.g. insulin-like growth factor binding protein) were upregulated in the PTB experiment and downregulated in the hypoxic experiment, and 3 genes (e.g. c-kit tyrosine kinase) were downregulated in the PTB and upregulated in the hypoxic experiment.

Conclusion/Significance

Pressure load of the right ventricle induces a marked shift in the gene expression, which in case of the metabolic genes appears compensated at the protein level, while both expression of genes and proteins of importance for myocardial function and remodelling are altered by the increased pressure load of the right ventricle. These findings imply that treatment of pulmonary hypertension should also aim at reducing right ventricular pressure.